Field
Aspects of the present invention generally relate to an information processing apparatus and a control method for the information processing apparatus.
Description of the Related Art
Conventional information processing apparatuses control power in some levels to reduce power consumption when not operating. As discussed in Japanese Patent Application Laid-Open No. 2009-96047, the number of power-OFFs/ONs is specified for a hard disk drive (HDD). An information processing apparatus needs to perform power control to lower the power effectively when not operating, while controlling the number of interruptions of the power to a system part including the HDD, to save the lifetime of the HDD.
In this connection, a central processing unit (CPU) is configured to count the number of power-OFFs/ONs of an HDD, and not to power off the HDD until a predetermined time elapses after a shift to a power save mode. Specifically, when not operating, an information processing apparatus shifts to a first power save mode by powering off devices including the HDD, if the number of power-OFFs/ONs of the HDD is below a specified number. If the number of power-OFFs/ONs of the HDD exceeds the specified number, the information processing apparatus shifts to a second power save mode by powering off some of the devices except for the HDD, while keeping the HDD powered on. Such a known technique can enhance power efficiency, and prevent the product lifetime of the information processing apparatus from being reduced by the lifetime of the HDD.
However, in the second power save mode, a load current decreases, and a voltage supplied to the HDD varies. Therefore, there is such an issue that an output voltage variation, which occurs due to an output current variation of a power supply device, needs to be suppressed to meet a specified input voltage for the HDD.